Kangwon National University

About: Kangwon National University is a education organization based out in Chuncheon, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 9836 authors who have published 20002 publications receiving 393562 citations. The organization is also known as: KNU.

Effects of prenylated flavonoids and biflavonoids on lipopolysaccharide-induced nitric oxide production from the mouse macrophage cell line RAW 264.7.

Abstract: Certain flavonoid derivatives possess anti-inflammatory activity in vitro and in vivo. Besides their antioxidative properties and effects on the arachidonic acid metabolism including cyclooxygenase/lipoxygenase inhibition, some flavones and flavonols were previously found to show inhibitory activity on nitric oxide production by inducible nitric oxide synthase (iNOS; NOS type 2) through suppression of iNOS induction. As part of our continuing investigations, the effects of unique and minor flavonoids (prenylated flavonoids and biflavonoids) on nitric oxide production from lipopolysaccharide-induced macrophage cell line (RAW 264.7) were evaluated in order to establish their inhibitory activity on NO production and correlate this action with their in vivo anti-inflammatory potential. Among the derivatives tested, prenylated compounds including morusin, kuwanon C, and sanggenon D and biflavonoids such as bilobetin and ginkgetin were found to inhibit NO production from lipopolysaccharide (LPS)-induced RAW 264.7 cells at > 10 microM. Inhibition of nitric oxide production was mediated by suppression of iNOS enzyme induction but not by direct inhibition of iNOS enzyme activity. An exception was echinoisoflavanone that inhibited iNOS enzyme activity (IC50 = 83 microM) and suppressed iNOS enzyme induction as well. While most prenylated derivatives showed cytotoxicity to RAW cells at 10-100 microM, all biflavonoids tested were not cytotoxic. Since nitric oxide (NO) produced by inducible NO synthase (iNOS) plays an important role in inflammatory disorders, inhibition of NO production by these flavonoids may contribute, at least in part, to their anti-inflammatory and immunoregulating potential in vivo.

Search for the Standard Model Higgs Boson in the Decay Channel H→ZZ→4l in pp Collisions at √s=7 TeV

Abstract: A search for a Higgs boson in the four-lepton decay channel H→ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range of 110 100 GeV (with 13 below 160 GeV), while 67.1±6.0 (9.5±1.3) events are expected from background. The four-lepton mass distribution is consistent with the expectation of standard model background production of ZZ pairs. Upper limits at 95% confidence level exclude the standard model Higgs boson in the ranges of 134–158 GeV, 180–305 GeV, and 340–465 GeV. Small excesses of events are observed around masses of 119, 126, and 320 GeV, making the observed limits weaker than expected in the absence of a signal.

Heavy metal immobilization in soil near abandoned mines using eggshell waste and rapeseed residue.

Abstract: Heavy metal contamination of agricultural soils has received great concern due to potential risk to human health. Cadmium and Pb are largely released from abandoned or closed mines in Korea, resulting in soil contamination. The objective of this study was to evaluate the effects of eggshell waste in combination with the conventional nitrogen, phosphorous, and potassium fertilizer (also known as NPK fertilizer) or the rapeseed residue on immobilization of Cd and Pb in the rice paddy soil. Cadmium and Pb extractabilities were tested using two methods of (1) the toxicity characteristics leaching procedure (TCLP) and (2) the 0.1 M HCl extraction. With 5 % eggshell addition, the values of soil pH were increased from 6.33 and 6.51 to 8.15 and 8.04 in combination with NPK fertilizer and rapeseed residue, respectively, compared to no eggshell addition. The increase in soil pH may contribute to heavy metal immobilization by altering heavy metals into more stable in soils. Concentrations of TCLP-extracted Cd and Pb were reduced by up to 67.9 and 93.2 % by addition of 5 % eggshell compared to control. For 0.1 M HCl extraction method, the concentration of 0.1 M HCl-Cd in soils treated with NPK fertilizer and rapeseed residue was significantly reduced by up to 34.01 and 46.1 %, respectively, with 5 % eggshell addition compared to control. A decrease in acid phosphatase activity and an increase in alkaline phosphatase activity at high soil pH were also observed. Combined application of eggshell waste and rapeseed residue can be cost-effective and beneficial way to remediate the soil contaminated with heavy metals.